Car: 2000 Subaru Legacy GT Limited w/ 2.5L H4 MPI Modifications:None (As far as I know) Problem Description: I posted last week about where to go to get a head gasket replaced. I ended up taking my car to RS Motors for the repair. They disassembled the engine and took the passenger side head off. Apparently the previous owner had attempted to fix the head gaskets himself and in the process had stripped one of the center head stud holes. He had tried to fix it by putting in a helicoil and then putting silicone around the gasket. The guys at RS said that since that hole was stripped out I would need to get an entire new motor as the problem was unfixable. I did some research on google and it seems like lots of people are able to fix this problem without getting a new engine. My question is, is there something about this particular engine that means that this cannot be fixed or were the guys at RS wrong and this is in fact a fixable issue? Thanks for your help!
Did they say it isn't fixable or it isn't worth fixing? If interested, you could talk to a machine shop to get their opinion. Dave at metro engine is top notch. http://www.metroengineservice.com/
From what I understood they said it wasn't fixable. I don't know all that much about these things but I asked if the hole could be retapped and he said something about how the pressure that's on those bolts means that they cannot be retapped. This seemed pretty ludicrous to me so I figured I'd ask the question.
I have tried to Helicoil a head stud hole before using two coils stacked on each other and it couldn't hold the 80+ foot pounds that the final steps of the torque procedure called for. The only option is to take the rotating assembly out and put it in another good case. The other option would be what Phi11 suggested but that would be costly as well as those types of studs are not cheap and the cases need to be taken apart to be tapped properly. Good luck
You can time-sert it and get the original torque rating, they have a kit for blocks that have been previously helicoiled as well . I believe it's in the $75-100 range, so a lot more than a helicoil but a lot less than a new block/labor: http://www.timesert.com/html/universalheadbolt.html
When you install a helicoil to fix the original thread, you have the drill that hole bigger to accept the helicoil. The helicoil takes that gap between the now bigger hole than original and puts it back to stock size. Usually works just fine if done properly. Problem is when it's not done properly or over torque, It will pull the threads back out again. Making the fixed hole even bigger. There is not helicoil for a helicoil. You will have to drill that hole yet bigger again then somehow try to build it back. Someone mentioned a bigger stud kit. It's worth a try if that hole will take it. Yes we can still be wrong.
The timesert kit is 450 by itself without machine shop labor, so probably better off finding a usable block.
